Last week I reported on a new
study by the Belgium Royal Meteorological Institute that stated the effects
of CO2 on world temperatures had been "grossly overstated". The
RMI's conclusion is supported by a pair of recent papers, both of which
severely downgrade the warming effect of carbon dioxide.
The first is by atmospheric scientist Stephen Schwartz, of Brookhaven
National Labs. Entitled, "Heat Capacity,
Time Constant, and Sensitivity of Earth's Climate System", the paper
is based on more accurate estimates of feedback processes in the Earth's
atmosphere. It concludes the IPCC estimate of 2 - 4.5C degrees warming
(from the anticipated 1900-2100 doubling of CO2 levels) is much too high,
and the actual figure should be closer to 1.1 degree.
The conclusion is very significant as we've already experienced
some 0.7 degrees of that warming. That means over the next century, only
an additional 0.4 degrees warming is expected. And after that,
the warming effect will nearly vanish.
The reason why is CO2 only absorbs in a very narrow band of infrared.
Climatologist Timothy Ball, who was not associated with this study, explains
with an analogy: "The relationship between temperature and CO2 is
like painting a window black to block sunlight. The first coat blocks most of
the light. Second and third coats reduce very little more. Current CO2 levels
are like the first coat of black paint."
The second
study is by Chinese researchers Lin Zhen-Shan and Sun Xian. Using a
technique called Empirical Mode Decomposition (EMD), they decoded temperature
changes into three natural cycles-- 6-8 years, 20 years, and 60-years, along
with a fourth signal, a non-periodic rising trend, which they associated with
CO2-based warming. They found that the largest effect on
temperature change was due to these natural cycles, and that the CO2-based
trend could only be responsible for a maximum of 40% of the warming attributed
to it.
Most astonishingly, they concluded that global cooling
will result for at least the next two decades, as the longer cycles are now
both in downward motion.
The factor all three of the above studies have in common? That CO2's
role has been massively overstated. The political consequences of this
are widespread-- is it worth spending trillions of dollars to reduce emissions
of a gas that will have almost no effect over the next century, and essentially
none at all after that?